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An Initial Look at Federal Offices of Research and Technology Applications
No full textIn Science-The Endless Frontier, Vannevar Bush wrote that reaping the potential benefits of science conducted at federal laboratories requires the discoveries made in the laboratories be transferred to society. In federal laboratories, Offices of Research and Technology Applications (ORTAs) are tasked with transferring laboratory-developed technologies to the market, allowing society to reap the benefits provided by scientific investments. In fiscal year 2016, the Technology Partnerships Office of the National Institute of Standards and Technology (NIST) conducted a first-of-its-kind survey of the ORTAs of more than 50 federal laboratories to obtain information on their organization and operation. We present descriptive analyses of the responses to this survey in two topical areas: organizational characteristics and technology transfer characteristics. We disaggregated the data across the dimension of budget size to describe similarities and differences in responses across the budget categories. Among the relationships we observed, we found that ORTAs with larger technology transfer budgets report higher frequencies of conducting internal technology transfer activities, such as patent prosecution (e.g., drafting patents, filing patent applications, and responding to actions from the patent office) and market analysis. Additionally, we provide context to the data by summarizing the relevant research on ORTAs at universities, and we present potential inferences that may be drawn from that body of research and applied to the data on ORTAs at federal laboratories
Erratum: Improved First-Principles Calculation of the Third Virial Coefficient of Helium
No full textThe calculations of C(T) for 3He in the original paper were in error at the lowest temperatures due to an incorrect accounting for the quantum statistics of fermions, as explained in Ref. The calculations for 4He are not affected by this error
Fused Filament Fabrication Printer Modified to Dispense Cement Paste for Concrete Additive Manufacturing Studies
No full textAdditive manufacturing (AM) with cement-based materials is an emerging technology that has the potential to revolutionize concrete construction. The placement process is quite complex, requiring sufficient flow properties as the material leaves the nozzle, and sufficient stiffening properties before the subsequent layer is placed. Precise control of material proportions and in-line monitoring of the time-dependent rheology are required to ensure the successful adoption of AM in the concrete construction community. To facilitate the study of the rheological properties of cementitious materials, as they pertain to AM, a commercial bench-top fused filament fabrication three-dimensional (3-D) printer was modified to dispense cement paste mixtures. Modifications included the design and assembly of a pumping system and software modifications to the 3-D printer's firmware that were necessary to accommodate the new hardware. After assembly, a series of tests were conducted to verify machine movements and to calibrate the number of step pulses required per unit volume of extruded paste. The resulting software modifications and configuration files are publicly available
Parallel Generalized Real Symmetric-Definite Eigenvalue Problem
No full textA computationally fast Fortran 90+ quadruple precision portable parallel GRSDEP (generalized real symmetric-definite eigenvalue problem) package suitable for large (80,000 x 80,000 or greater) dense matrices is discussed in this paper
Improvised Long Test Lengths via Stitching Scale Bar Method:Performance Evaluation of Terrestrial Laser Scanners per ASTM E3125-17
No full textPeriodic performance evaluation is a critical issue for ensuring the reliability of data from terrestrial laser scanners (TLSs). With the recent introduction of the ASTM E3125-17 standard, there now exist standardized test procedures for this purpose. Point-to-point length measurement is one test method described in that documentary standard. This test is typically performed using a long scale bar (typically 2 m or longer) with spherical targets mounted on both ends. Long scale bars can become unwieldy and vary in length due to gravity loading, fixture forces, and environmental changes. In this paper, we propose a stitching scale bar (SSB) method in which a short scale bar (approximately 1 m or smaller) can provide a spatial length reference several times its length. The clear advantages of a short scale bar are that it can be calibrated in a laboratory and has potential long-term stability. An essential requirement when stitching a short scale bar is that the systematic errors in TLSs do not change significantly over short distances. We describe this requirement in this paper from both theoretical and experimental perspectives. Based on this SSB method, we evaluate the performance of a TLS according to the ASTM E3125-17 standard by stitching a 1.15 m scale bar to form a 2.3 m reference length. For comparison, a single 2.3 m scale bar is also employed for direct measurements without stitching. Experimental results show a maximum deviation of 0.072 mm in length errors between the two approaches, which is an order of magnitude smaller than typical accuracy specifications for TLSs
Performance of Test Supermartingale Confidence Intervals for the Success Probability of Bernoulli Trials
No full textGiven a composite null hypothesis H-0, test supermartingales are non-negative supermartingales with respect to H(0 )with an initial value of 1. Large values of test supermartingales provide evidence against H-0. As a result, test supermartingales are an effective tool for rejecting H-0, particularly when the p-values obtained are very small and serve as certificates against the null hypothesis. Examples include the rejection of local realism as an explanation of Bell test experiments in the foundations of physics and the certification of entanglement in quantum information science. Test supermartingales have the advantage of being adaptable during an experiment and allowing for arbitrary stopping rules. By inversion of acceptance regions, they can also be used to determine confidence sets. We used an example to compare the performance of test supermartingales for computing p-values and confidence intervals to Chernoff-Hoeffding bounds and the ""exact"" p-value. The example is the problem of inferring the probability of success in a sequence of Bernoulli trials. There is a cost in using a technique that has no restriction on stopping rules, and, for a particular test supermartingale, our study quantifies this cost
Microscale Mapping of Structure and Stress in Barium Titanate
No full textCross-correlation of electron backscatter diffraction (EBSD) patterns was used to generate rotation, strain, and stress maps of single-crystal tetragonal barium titanate (BaTiO3) containing isolated, small, sub-micrometer a domains separated from a c- domain matrix by 90 degrees domain boundaries. Spatial resolution of about 30 nm was demonstrated over 5 mu m maps, with rotation and strain resolutions of approximately 10(-4). The magnitudes of surface strains and, especially, rotations peaked within and adjacent to isolated domains at values of approximately 10(-)(2), i.e., the tetragonal distortion of BaTiO3. The conjugate stresses between a domains peaked at about 1 GPa, and principal stress analysis suggested that stable microcrack formation in the c domain was possible. The results clearly demonstrate the applicability of EBSD to advanced multilayer ceramic capacitor reliability and strongly support the coupling between the electrical performance and underlying mechanical state of BaTiO3-containing devices
Shock Measurements Based on Pendulum Excitation and Laser Doppler Velocimetry: Primary Calibration by SI-Traceable Distance Measurements
No full textA new method is described to provide a primary calibration of shock measurements produced by a shock measurement system consisting of pendulum excitation and laser Doppler velocimetry. The method uses the laser Doppler velocimeter to determine the total distance traveled by a rigid block that slides along a Teflon (fluorocarbon) channel after being struck by a pendulum head, and the resulting distance is compared to the distance measured by an SI-traceable length measurement. The instantaneous velocity of the block is measured by the velocimeter and is used to calculate the displacement of the block by integrating the velocity data. The result is compared to the displacement measured using calibrated rulers and calipers. The method was applied to an independently calibrated commercial velocimeter for impact accelerations ranging from 2000 to 30,000 m/s(2). The results of the independent mechanicaldisplacement measurements agreed with those from the commercial velocimeter to within +/- 0.3 %, with better agreement above accelerations of order 10,000 m/s(2) to within +/- 0.1 %. A conservative, upper-bound, uncertainty analysis included the effects of noise and other random errors, as well as type B estimates for systematic errors from occasional momentary demodulation failures (dropouts), use of a different number of rulers before and after shock distance measurement, and the relative frequency response of the velocimeter
Characterization of 3-Dimensional Printing and Casting Materials for use in Magnetic Resonance Imaging Phantoms at 3 T
No full textImaging phantoms are used to calibrate and validate the performance of magnetic resonance imaging (MRI) systems. Many new materials have been developed for additive manufacturing (three-dimensional [3D] printing) processes that may be useful in the direct printing or casting of dimensionally accurate, anatomically accurate, patient-specific, and/or biomimetic MRI phantoms. The T-1, T-2, and T-2* spin relaxation times of polymer samples were tested to discover materials for use as tissue mimics and structures in MRI phantoms. This study included a cohort of polymer compounds that was tested in cured form. The cohort consisted of 101 standardized polymer samples fabricated from: two-part silicones and polyurethanes used in commercial casting processes; one-part optically cured polyurethanes used in 3D printing; and fused deposition thermoplastics used in 3D printing. The testing was performed at 3 T using inversion recovery, spin echo, and gradient echo sequences for T-1, T-2, and T-2*, respectively. T-1, T-2, and T-2* values were plotted with error bars to allow the reader to assess how well a polymer matches a tissue for a specific application. A correlation was performed between T-1, T-2, T-2* values and material density, elongation, tensile strength, and hardness. Two silicones, SI_XP-643 and SI_P-45, may be usable mimics for reported liver values; one silicone, SI_XP-643, may be a useful mimic for muscle; one silicone, SI_XP-738, may be a useful mimic for white matter; and four silicones, SI_P-15, SI_GI-1000, SI_GI-1040, and SI_GI-1110, may be usable mimics for spinal cord. Elongation correlated to T-2 (p = 0.0007), tensile strength correlated to T-1 (p = 0.002), T-2 (p = 0.0003), and T-2* (p = 0.003). The 80 samples not providing measurable signal with T-1, T-2, T-2* relaxation values too short to measure with the standard sequences, may be useful for MRI-invisible fixturing and medical devices at 3 T
JOHN L. GROSS
No full textTENURE AT NBS/NIST: 1983-2016
INDUCTED into the NIST Gallery of Distinguished Scientists, Engineers, and Administrators: 2020
Birth: 1947, Philadelphia, Pennsylvania
EDUCATION:
Cornell University, BS (Civil and Environmental Engineering), 1969
Cornell University, ME (Civil and Environmental Engineering), 1970
Cornell University, PhD (Civil and Environmental Engineering), 1980
CITATION: For advancing understanding of how and why structures fail - using disaster investigations, developing novel laboratory tools and facilities, and leading standards improvements to make buildings and other structures safer
POSITIONS HELD AT NBS/NIST:
Research Structural Engineer, Building and Fire Research Laboratory (BFRL)/Engineering Laboratory, 1983-2016
Leader, Structures Group, Materials and Construction Research Division, BFRL, 1998-2004
HONORS:
Building and Fire Research Laboratory Communicator Award (1988 and 2000)
Leonard C. Wason Medal, American Concrete Institute (1988)
NIST Bronze Medal (2001)
DoC Engineer of the Year and Top 10 Finalist for Federal Engineer of the Year, National Society of Professional Engineers (2001)
Raymond C. Reese Research Prize, American Society of Civil Engineers (2001)
U.S. Department of Commerce Gold Medal (2005)
NIST Special Act Award (2008)
The 2010 Power List - Structural Engineering and Design magazine (2010)
Fellow, American Society of Civil Engineers (2014)
MEMBERSHIPS:
American Institute of Steel Construction
American Society of Civil Engineers
ISO/TC 92/SC 4/WG 12 Structures in Fire Working group
Licensed Professional Engineer
PUBLICATIONS:
More than 75 publications and one patent including:
Gross, J., et al., AISC Steel Design Guide Series 12: Modification of Existing Welded Steel Moment Frame Connections for Seismic Resistance (2003)
Gross, J., et al., Final Report on the Collapse of the World Trade Center Towers and Final Report on the Collapse of the World Trade Center Building 7 (Gann, R.G., ed.), NIST NCSTAR 1 and 1A, Federal Building and Fire Safety Investigation of the World Trade Center Disaster (2005, 2008)
U.S. Patent 9,010,402 B2: Method and Apparatus for Interlocking Load Carrying Elements (April 21, 2015)
Bundy, M., Hamins, A., Gross, J., et al., “Structural Fire Experimental Capabilities at the NIST National Fire Research Laboratory”, Fire Technology 52, 959-966 (2016